Microcosmic salt reacts with coloured ions to form characteristic bead which is due to formation of

Options

A. Borates
B. Metaphosphates
C. Metaborates
D. Phosphates

Answer

To solve the question about the reaction of microcosmic salt with colored ions, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Microcosmic Salt**:
- Microcosmic salt is chemically known as sodium ammonium hydrogen phosphate, with the formula NaNH4HPO4.

2. **Understand the Reaction**:
- When microcosmic salt is heated, it decomposes to form sodium metaphosphate, ammonia, and water. The reaction can be summarized as:
\[ \text{NaNH}_4\text{HPO}_4 \xrightarrow{\text{heat}} \text{NaPO}_3 + \text{NH}_3 + \text{H}_2\text{O} \]
- Here, sodium metaphosphate (NaPO3) is the key product.

3. **Formation of Characteristic Bead**:
- The characteristic bead formed when microcosmic salt reacts with colored ions is primarily due to the formation of sodium metaphosphate. This bead is transparent and colorless.

4. **Evaluate the Options**:
- The question provides several options regarding the type of compound formed:
- Option 1: Borate (Incorrect)
- Option 2: Metaphosphate (Correct)
- Option 3: Metaborate (Incorrect)
- Option 4: Phosphate (Incorrect)
- Since the correct product formed is sodium metaphosphate, the correct answer is option 2.

5. **Conclusion**:
- Therefore, the characteristic bead formed is due to the formation of metaphosphate.

### Final Answer:
The characteristic bead formed when microcosmic salt reacts with colored ions is due to the formation of **metaphosphate**.

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